We report on multi-spacecraft measurements of a solar energetic particle (SEP) event that occurred on 13 March 2023. The Parker Solar Probe (PSP) mission was situated on the far side of the Sun as seen from Earth at a radial distance of only 49 solar radii and observed a very strong event including the associated CME and its shock passing over the spacecraft only four hours after the solar eruption. Solar Orbiter, BepiColombo, STEREO A, near-Earth spacecraft, and MAVEN at Mars were all situated within 50 degrees in longitude, and observed the event as well, proving its widespread character. Clear signatures of shock-driven energetic storm particle events were present at Solar Orbiter, STEREO A, and near-Earth spacecraft suggesting that the interplanetary CME-driven shock had a longitudinal extent of about 160 degrees. However, the solar event was accompanied by a series of pre-event CMEs and comparison with ENLIL simulation results suggest that the ESP events were associated with shocks driven by other CMEs. This scenario of particle re-acceleration at different pre-event-associated shocks, provides a new scenario for the generation of widespread SEP events.

The widespread SEP event of 17 April 2021 was observed by five longitudinally well-separated observers in the inner heliosphere covering distances to the Sun from 0.42 to 1 au: BepiColombo, Parker Solar Probe, Solar Orbiter, STEREO A, and close-to-Earth spacecraft. The event, which produced relativistic electrons and protons, was associated with a complex and long-lasting solar eruption involving a long-duration flare, a medium-fast Coronal Mass Ejection (CME), an EUV wave and a complex solar radio burst activity lasting for 40 minutes including type II bursts, marking the presence of a shock, as well as four distinct groups of type III bursts. Our comprehensive analysis of the multi-spacecraft in-situ and remote-sensing observations suggests different source regions for the electron and proton SEP event with a stronger shock contribution for the proton event and a more likely flare-related source of the electron event. We furthermore determine that the four distinct injection episodes, marked by the radio type III burst groups, cover a longitudinal range of about 110° and were a main ingredient for the wide SEP spread. We consider this a new scenario that must be taken into account as a potential contributor to widespread SEP events.

The 5 September 2022 SEP event observed by Parker Solar Probe yielded some of the highest intensities in high energy electrons observed at the instrument since its launch in 2018. For this paper, we will examine the high energy electron signals detected by the EPI-Hi HET instrument to measure the spectra, the time-evolution of the spectra, and anisotropies in electrons during the event. We will examine the HET electron measurements and compare them with the proton measurements. We will also explain in detail the calculation of the electron spectra during periods of very high count rate.